Any member of two unrelated groups of fishes: freshwater species in the genus Brachydanio (family Cyprinidae) and saltwater species in the genus Pterois (family Scorpaenidae).
The zebra danio ( Brachydanio rerio ), a popular freshwater aquarium fish originally from Asia, grows to about 1.5 in. (4 cm) long and has dark blue and silvery longitudinal stripes. The distinctive saltwater zebra fishes ( Pterois ), used in marine aquariums, have extremely large pectoral fins, numerous extremely poisonous spines, and colourful vertical stripes. Some species are more commonly known as lionfish and turkeyfish.